Impact Of High-Velocity Circuit Training On Physical Performance, Cognition And Retinal Microvasculature In Older Persons.

Although high-velocity circuit training (HVCT) appears to improve age-related cognitive decline, the underlying mechanisms are poorly understood. An accessible tool for assessing changes in the cerebral microvasculature is optical imaging of the retinal microvasculature. PURPOSE: This study examined the impact of 6 months of HVCT on oxygen consumption (6-min walk test: 6MWT), chest press (CPPP) and leg press (LPPP) peak power, retinal capillary density (RCD) and cognition (trail-making tests A and B (TMT-A,TMT-B)), NIH Fluid Cognition Composite Score (FCCS) and components of the Hopkins Verbal Learning test (HVLT). METHODS: 30 subjects (73.0 ± 6.6 y) were randomly assigned to HVCT (n = 16) or a group receiving no formal training (CON; n = 14) for 6 months. HVCT employed 3 circuits of 11 exercises performed on pneumatic machines with full speed concentric and controlled eccentric movements. Recovery between exercises was minimalized. Mixed repeated measures ANOVA with LSD post hoc testing were used to determine significant differences or interactions for all variables. RESULTS: No significant main effects or interactions were seen for the 6MWT; however, the HVCT group alone increased CPPP (MD ± SE = 53.29 ± 18.90 W; CI: 14.18 W, 92.39 W; p < .010) and LPPP (MD ± SE = 130.8 ± 35.7 W; CI: 57.4 W, 204.2 W; p < .001). Although no change was seen in the FCCS, significant improvements were made by the HVCT group in the TMT-A (MD ± SE = 5.70 ± 1.46 s; CI: 2.71 s, 8.70 s; p < .001) and TMT-B (MD ± SE = 10.15 ± 5.41 s; CI: -0.92 s, 21.23 s; p = .019). Further, significant increases were seen in the sample for 3 of the 6 components of the HVLT for both groups. Finally, significant decreases were seen in RCD by the trained group only (MD ± SE = -0.011 ± 0.003; CI: -0.180, -0.0046; p = .002). CONCLUSIONS: HVCT had a positive impact on processing speed and retinal microvascular density, as well as upper and lower body mechanical power, but not in 6MWT, indicating the positive impact of resistance training on cognitive performance and cerebral microvasculature as shown previously with other interval training programs.